useful sed one liner in bash

I was about to upload some documents to my company's wiki that someone else wrote. Upload failed! For some odd reason they chose to use a '+' instead of a space or under bar in the filename. Here is how I fixed it.

for i in `ls -1`; do 
    new=`echo ${old} |sed -e 's/\+/\_/g'`
    echo "moving ${old} to ${new}"
    mv ${old} ${new}